Chore: Fix staticcheck issues (#28854)

* Chore: Fix issues reported by staticcheck

Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>

* Undo changes

Signed-off-by: Arve Knudsen <arve.knudsen@gmail.com>

pkg/api/ldap_debug_test.go

@@ -509,7 +509,7 @@ func TestPostSyncUserWithLDAPAPIEndpoint_WhenGrafanaAdmin(t *testing.T) {
 
 	expected := `
 	{
-		"error": "Did not find a user",
+		"error": "did not find a user",
 		"message": "Refusing to sync grafana super admin \"ldap-daniel\" - it would be disabled"
 	}
 	`

pkg/services/alerting/conditions/evaluator.go

@@ -35,12 +35,12 @@ type thresholdEvaluator struct {
 func newThresholdEvaluator(typ string, model *simplejson.Json) (*thresholdEvaluator, error) {
 	params := model.Get("params").MustArray()
 	if len(params) == 0 || params[0] == nil {
-		return nil, fmt.Errorf("Evaluator '%v' is missing the threshold parameter", HumanThresholdType(typ))
+		return nil, fmt.Errorf("evaluator '%v' is missing the threshold parameter", HumanThresholdType(typ))
 	}
 
 	firstParam, ok := params[0].(json.Number)
 	if !ok {
-		return nil, fmt.Errorf("Evaluator has invalid parameter")
+		return nil, fmt.Errorf("evaluator has invalid parameter")
 	}
 
 	defaultEval := &thresholdEvaluator{Type: typ}
@@ -113,7 +113,7 @@ func (e *rangedEvaluator) Eval(reducedValue null.Float) bool {
 func NewAlertEvaluator(model *simplejson.Json) (AlertEvaluator, error) {
 	typ := model.Get("type").MustString()
 	if typ == "" {
-		return nil, fmt.Errorf("Evaluator missing type property")
+		return nil, fmt.Errorf("evaluator missing type property")
 	}
 
 	if inSlice(typ, defaultTypes) {
@@ -128,7 +128,7 @@ func NewAlertEvaluator(model *simplejson.Json) (AlertEvaluator, error) {
 		return &noValueEvaluator{}, nil
 	}
 
-	return nil, fmt.Errorf("Evaluator invalid evaluator type: %s", typ)
+	return nil, fmt.Errorf("evaluator invalid evaluator type: %s", typ)
 }
 
 func inSlice(a string, list []string) bool {

pkg/services/alerting/conditions/query.go

@@ -113,7 +113,7 @@ func (c *QueryCondition) executeQuery(context *alerting.EvalContext, timeRange *
 	}
 
 	if err := bus.Dispatch(getDsInfo); err != nil {
-		return nil, fmt.Errorf("Could not find datasource %v", err)
+		return nil, fmt.Errorf("could not find datasource: %w", err)
 	}
 
 	req := c.getRequestForAlertRule(getDsInfo.Result, timeRange, context.IsDebug)
@@ -159,7 +159,7 @@ func (c *QueryCondition) executeQuery(context *alerting.EvalContext, timeRange *
 	resp, err := c.HandleRequest(context.Ctx, getDsInfo.Result, req)
 	if err != nil {
 		if err == gocontext.DeadlineExceeded {
-			return nil, fmt.Errorf("Alert execution exceeded the timeout")
+			return nil, fmt.Errorf("alert execution exceeded the timeout")
 		}
 
 		return nil, fmt.Errorf("tsdb.HandleRequest() error %v", err)

pkg/services/alerting/notifier.go

@@ -2,7 +2,6 @@ package alerting
 
 import (
 	"context"
-	"errors"
 	"fmt"
 	"time"
 
@@ -281,7 +280,7 @@ func (n *notificationService) getNeededNotifiers(orgID int64, notificationUids [
 func InitNotifier(model *models.AlertNotification) (Notifier, error) {
 	notifierPlugin, found := notifierFactories[model.Type]
 	if !found {
-		return nil, errors.New("Unsupported notification type")
+		return nil, fmt.Errorf("unsupported notification type %q", model.Type)
 	}
 
 	return notifierPlugin.Factory(model)

pkg/services/alerting/test_notification.go

@@ -89,7 +89,7 @@ func createTestEvalContext(cmd *NotificationTestCommand) *EvalContext {
 	}
 	ctx.IsTestRun = true
 	ctx.Firing = true
-	ctx.Error = fmt.Errorf("This is only a test")
+	ctx.Error = fmt.Errorf("this is only a test")
 	ctx.EvalMatches = evalMatchesBasedOnState()
 
 	return ctx

pkg/services/alerting/test_rule.go

@@ -45,7 +45,7 @@ func handleAlertTestCommand(cmd *AlertTestCommand) error {
 		}
 	}
 
-	return fmt.Errorf("Could not find alert with panel id %d", cmd.PanelID)
+	return fmt.Errorf("could not find alert with panel ID %d", cmd.PanelID)
 }
 
 func testAlertRule(rule *Rule) *EvalContext {

pkg/services/guardian/guardian.go

@@ -10,8 +10,8 @@ import (
 )
 
 var (
-	ErrGuardianPermissionExists = errors.New("Permission already exists")
-	ErrGuardianOverride         = errors.New("You can only override a permission to be higher")
+	ErrGuardianPermissionExists = errors.New("permission already exists")
+	ErrGuardianOverride         = errors.New("you can only override a permission to be higher")
 )
 
 // DashboardGuardian to be used for guard against operations without access on dashboard and acl

pkg/services/ldap/ldap.go

@@ -73,10 +73,10 @@ const UsersMaxRequest = 500
 var (
 
 	// ErrInvalidCredentials is returned if username and password do not match
-	ErrInvalidCredentials = errors.New("Invalid Username or Password")
+	ErrInvalidCredentials = errors.New("invalid username or password")
 
 	// ErrCouldNotFindUser is returned when username hasn't been found (not username+password)
-	ErrCouldNotFindUser = errors.New("Can't find user in LDAP")
+	ErrCouldNotFindUser = errors.New("can't find user in LDAP")
 )
 
 // New creates the new LDAP connection

pkg/services/login/errors.go

@@ -3,7 +3,7 @@ package login
 import "errors"
 
 var (
-	ErrInvalidCredentials = errors.New("Invalid Username or Password")
-	ErrUsersQuotaReached  = errors.New("Users quota reached")
-	ErrGettingUserQuota   = errors.New("Error getting user quota")
+	ErrInvalidCredentials = errors.New("invalid username or password")
+	ErrUsersQuotaReached  = errors.New("users quota reached")
+	ErrGettingUserQuota   = errors.New("error getting user quota")
 )

pkg/services/multildap/multildap.go

@@ -27,10 +27,10 @@ var ErrInvalidCredentials = ldap.ErrInvalidCredentials
 var ErrCouldNotFindUser = ldap.ErrCouldNotFindUser
 
 // ErrNoLDAPServers is returned when there is no LDAP servers specified
-var ErrNoLDAPServers = errors.New("No LDAP servers are configured")
+var ErrNoLDAPServers = errors.New("no LDAP servers are configured")
 
 // ErrDidNotFindUser if request for user is unsuccessful
-var ErrDidNotFindUser = errors.New("Did not find a user")
+var ErrDidNotFindUser = errors.New("did not find a user")
 
 // ServerStatus holds the LDAP server status
 type ServerStatus struct {

pkg/services/ngalert/eval.go

@@ -109,12 +109,12 @@ func (ng *AlertNG) LoadAlertCondition(dashboardID int64, panelID int64, conditio
 
 	blob, err := getDashboardQuery.Result.Data.MarshalJSON()
 	if err != nil {
-		return nil, errors.New("Failed to marshal dashboard JSON")
+		return nil, errors.New("failed to marshal dashboard JSON")
 	}
 	var dash minimalDashboard
 	err = json.Unmarshal(blob, &dash)
 	if err != nil {
-		return nil, errors.New("Failed to unmarshal dashboard JSON")
+		return nil, errors.New("failed to unmarshal dashboard JSON")
 	}
 
 	condition := Condition{}
@@ -144,7 +144,7 @@ func (ng *AlertNG) LoadAlertCondition(dashboardID int64, panelID int64, conditio
 				}
 
 				if ds == nil {
-					return nil, errors.New("No datasource reference found")
+					return nil, errors.New("no datasource reference found")
 				}
 
 				if queryDatasource == "" {
@@ -192,7 +192,7 @@ func (ng *AlertNG) LoadAlertCondition(dashboardID int64, panelID int64, conditio
 func (c *Condition) Execute(ctx AlertExecCtx, fromStr, toStr string) (*ExecutionResults, error) {
 	result := ExecutionResults{}
 	if !c.IsValid() {
-		return nil, fmt.Errorf("Invalid conditions")
+		return nil, fmt.Errorf("invalid conditions")
 	}
 
 	request := &tsdb.TsdbQuery{
@@ -212,7 +212,7 @@ func (c *Condition) Execute(ctx AlertExecCtx, fromStr, toStr string) (*Execution
 
 	conditionResult := resp.Results[c.RefID]
 	if conditionResult == nil {
-		err = fmt.Errorf("No GEL results")
+		err = fmt.Errorf("no GEL results")
 		result.Error = err
 		return &result, err
 	}
@@ -234,24 +234,24 @@ func EvaluateExecutionResult(results *ExecutionResults) (Results, error) {
 	for _, f := range results.Results {
 		rowLen, err := f.RowLen()
 		if err != nil {
-			return nil, fmt.Errorf("Unable to get frame row length")
+			return nil, fmt.Errorf("unable to get frame row length")
 		}
 		if rowLen > 1 {
-			return nil, fmt.Errorf("Invalid frame %v: row length %v", f.Name, rowLen)
+			return nil, fmt.Errorf("invalid frame %v: row length %v", f.Name, rowLen)
 		}
 
 		if len(f.Fields) > 1 {
-			return nil, fmt.Errorf("Invalid frame %v: field length %v", f.Name, len(f.Fields))
+			return nil, fmt.Errorf("invalid frame %v: field length %v", f.Name, len(f.Fields))
 		}
 
 		if f.Fields[0].Type() != data.FieldTypeNullableFloat64 {
-			return nil, fmt.Errorf("Invalid frame %v: field type %v", f.Name, f.Fields[0].Type())
+			return nil, fmt.Errorf("invalid frame %v: field type %v", f.Name, f.Fields[0].Type())
 		}
 
 		labelsStr := f.Fields[0].Labels.String()
 		_, ok := labels[labelsStr]
 		if ok {
-			return nil, fmt.Errorf("Invalid frame %v: frames cannot uniquely be identified by its labels: %q", f.Name, labelsStr)
+			return nil, fmt.Errorf("invalid frame %v: frames cannot uniquely be identified by its labels: %q", f.Name, labelsStr)
 		}
 		labels[labelsStr] = true
 

pkg/services/notifications/mailer.go

@@ -105,7 +105,7 @@ func (ns *NotificationService) createDialer() (*gomail.Dialer, error) {
 	if ns.Cfg.Smtp.CertFile != "" {
 		cert, err := tls.LoadX509KeyPair(ns.Cfg.Smtp.CertFile, ns.Cfg.Smtp.KeyFile)
 		if err != nil {
-			return nil, fmt.Errorf("Could not load cert or key file. error: %v", err)
+			return nil, fmt.Errorf("could not load cert or key file: %w", err)
 		}
 		tlsconfig.Certificates = []tls.Certificate{cert}
 	}
@@ -159,7 +159,7 @@ func (ns *NotificationService) buildEmailMessage(cmd *models.SendEmailCommand) (
 		subjectText, hasSubject := subjectData["value"]
 
 		if !hasSubject {
-			return nil, fmt.Errorf("Missing subject in Template %s", cmd.Template)
+			return nil, fmt.Errorf("missing subject in template %s", cmd.Template)
 		}
 
 		subjectTmpl, err := template.New("subject").Parse(subjectText.(string))

pkg/services/notifications/notifications.go

@@ -63,7 +63,7 @@ func (ns *NotificationService) Init() error {
 	}
 
 	if !util.IsEmail(ns.Cfg.Smtp.FromAddress) {
-		return errors.New("Invalid email address for SMTP from_address config")
+		return errors.New("invalid email address for SMTP from_address config")
 	}
 
 	if setting.EmailCodeValidMinutes == 0 {

pkg/services/provisioning/dashboards/file_reader.go

@@ -20,7 +20,7 @@ import (
 
 var (
 	// ErrFolderNameMissing is returned when folder name is missing.
-	ErrFolderNameMissing = errors.New("Folder name missing")
+	ErrFolderNameMissing = errors.New("folder name missing")
 )
 
 // FileReader is responsible for reading dashboards from disc and
@@ -41,7 +41,7 @@ func NewDashboardFileReader(cfg *config, log log.Logger) (*FileReader, error) {
 	if !ok {
 		path, ok = cfg.Options["folder"].(string)
 		if !ok {
-			return nil, fmt.Errorf("Failed to load dashboards. path param is not a string")
+			return nil, fmt.Errorf("failed to load dashboards, path param is not a string")
 		}
 
 		log.Warn("[Deprecated] The folder property is deprecated. Please use path instead.")

pkg/services/provisioning/notifiers/config_reader_test.go

@@ -314,7 +314,7 @@ func TestNotificationAsConfig(t *testing.T) {
 			cfgProvider := &configReader{log: log.New("test logger")}
 			_, err := cfgProvider.readConfig(unknownNotifier)
 			So(err, ShouldNotBeNil)
-			So(err.Error(), ShouldEqual, "Unsupported notification type")
+			So(err.Error(), ShouldEqual, `unsupported notification type "nonexisting"`)
 		})
 
 		Convey("Read incorrect properties", func() {

pkg/services/rendering/http_mode.go

@@ -72,7 +72,7 @@ func (rs *RenderingService) renderViaHttp(ctx context.Context, renderKey string,
 	resp, err := netClient.Do(req)
 	if err != nil {
 		rs.log.Error("Failed to send request to remote rendering service.", "error", err)
-		return nil, fmt.Errorf("Failed to send request to remote rendering service. %s", err)
+		return nil, fmt.Errorf("failed to send request to remote rendering service: %w", err)
 	}
 
 	// save response to file
@@ -87,7 +87,8 @@ func (rs *RenderingService) renderViaHttp(ctx context.Context, renderKey string,
 	// if we didn't get a 200 response, something went wrong.
 	if resp.StatusCode != http.StatusOK {
 		rs.log.Error("Remote rendering request failed", "error", resp.Status)
-		return nil, fmt.Errorf("Remote rendering request failed. %d: %s", resp.StatusCode, resp.Status)
+		return nil, fmt.Errorf("remote rendering request failed, status code: %d, status: %s", resp.StatusCode,
+			resp.Status)
 	}
 
 	out, err := os.Create(filePath)
@@ -103,7 +104,7 @@ func (rs *RenderingService) renderViaHttp(ctx context.Context, renderKey string,
 			return nil, ErrTimeout
 		}
 		rs.log.Error("Remote rendering request failed", "error", err)
-		return nil, fmt.Errorf("Remote rendering request failed.  %s", err)
+		return nil, fmt.Errorf("remote rendering request failed: %w", err)
 	}
 
 	return &RenderResult{FilePath: filePath}, err

pkg/services/rendering/interface.go

@@ -8,8 +8,8 @@ import (
 	"github.com/grafana/grafana/pkg/models"
 )
 
-var ErrTimeout = errors.New("Timeout error. You can set timeout in seconds with &timeout url parameter")
-var ErrNoRenderer = errors.New("No renderer plugin found nor is an external render server configured")
+var ErrTimeout = errors.New("timeout error - you can set timeout in seconds with &timeout url parameter")
+var ErrNoRenderer = errors.New("no renderer plugin found nor is an external render server configured")
 var ErrPhantomJSNotInstalled = errors.New("PhantomJS executable not found")
 
 type Opts struct {

pkg/services/rendering/plugin_mode.go

@@ -96,7 +96,7 @@ func (rs *RenderingService) renderViaPluginV2(ctx context.Context, renderKey str
 		return nil, err
 	}
 	if rsp.Error != "" {
-		return nil, fmt.Errorf("Rendering failed: %v", rsp.Error)
+		return nil, fmt.Errorf("rendering failed: %s", rsp.Error)
 	}
 
 	return &RenderResult{FilePath: pngPath}, err

pkg/services/sqlstore/alert.go

@@ -286,7 +286,7 @@ func SetAlertState(cmd *models.SetAlertStateCommand) error {
 		if has, err := sess.ID(cmd.AlertId).Get(&alert); err != nil {
 			return err
 		} else if !has {
-			return fmt.Errorf("Could not find alert")
+			return fmt.Errorf("could not find alert")
 		}
 
 		if alert.State == models.AlertStatePaused {

pkg/services/sqlstore/alert_notification.go

@@ -390,7 +390,7 @@ func UpdateAlertNotification(cmd *models.UpdateAlertNotificationCommand) error {
 		}
 
 		if sameNameQuery.Result != nil && sameNameQuery.Result.Id != current.Id {
-			return fmt.Errorf("Alert notification name %s already exists", cmd.Name)
+			return fmt.Errorf("alert notification name %q already exists", cmd.Name)
 		}
 
 		// delete empty keys
@@ -431,7 +431,7 @@ func UpdateAlertNotification(cmd *models.UpdateAlertNotificationCommand) error {
 		if affected, err := sess.ID(cmd.Id).Update(current); err != nil {
 			return err
 		} else if affected == 0 {
-			return fmt.Errorf("Could not update alert notification")
+			return fmt.Errorf("could not update alert notification")
 		}
 
 		cmd.Result = &current
@@ -578,7 +578,7 @@ func GetOrCreateAlertNotificationState(ctx context.Context, cmd *models.GetOrCre
 				}
 
 				if !exist {
-					return errors.New("Should not happen")
+					return errors.New("should not happen")
 				}
 
 				cmd.Result = nj

pkg/services/sqlstore/annotation.go

@@ -15,7 +15,7 @@ import (
 func validateTimeRange(item *annotations.Item) error {
 	if item.EpochEnd == 0 {
 		if item.Epoch == 0 {
-			return errors.New("Missing Time Range")
+			return errors.New("missing time range")
 		}
 		item.EpochEnd = item.Epoch
 	}
@@ -78,7 +78,7 @@ func (r *SqlAnnotationRepo) Update(item *annotations.Item) error {
 			return err
 		}
 		if !isExist {
-			return errors.New("Annotation not found")
+			return errors.New("annotation not found")
 		}
 
 		existing.Updated = timeNow().UnixNano() / int64(time.Millisecond)

pkg/services/sqlstore/login_attempt.go

@@ -39,12 +39,10 @@ func DeleteOldLoginAttempts(cmd *models.DeleteOldLoginAttemptsCommand) error {
 		var maxId int64
 		sql := "SELECT max(id) as id FROM login_attempt WHERE created < ?"
 		result, err := sess.Query(sql, cmd.OlderThan.Unix())
-
 		if err != nil {
 			return err
 		}
-		// nolint: gosimple
-		if result == nil || len(result) == 0 || result[0] == nil {
+		if len(result) == 0 || result[0] == nil {
 			return nil
 		}
 

pkg/services/sqlstore/sqlstore.go

@@ -116,7 +116,7 @@ func (ss *SqlStore) ensureMainOrgAndAdminUser() error {
 		systemUserCountQuery := models.GetSystemUserCountStatsQuery{}
 		err := bus.DispatchCtx(ctx, &systemUserCountQuery)
 		if err != nil {
-			return fmt.Errorf("Could not determine if admin user exists: %v", err)
+			return fmt.Errorf("could not determine if admin user exists: %w", err)
 		}
 
 		if systemUserCountQuery.Result.Count > 0 {
@@ -132,7 +132,7 @@ func (ss *SqlStore) ensureMainOrgAndAdminUser() error {
 			cmd.IsAdmin = true
 
 			if err := bus.DispatchCtx(ctx, &cmd); err != nil {
-				return fmt.Errorf("Failed to create admin user: %v", err)
+				return fmt.Errorf("failed to create admin user: %s", err)
 			}
 
 			ss.log.Info("Created default admin", "user", setting.AdminUser)
@@ -226,7 +226,7 @@ func (ss *SqlStore) buildConnectionString() (string, error) {
 		cnnstr = fmt.Sprintf("file:%s?cache=%s&mode=rwc", ss.dbCfg.Path, ss.dbCfg.CacheMode)
 		cnnstr += ss.buildExtraConnectionString('&')
 	default:
-		return "", fmt.Errorf("Unknown database type: %s", ss.dbCfg.Type)
+		return "", fmt.Errorf("unknown database type: %s", ss.dbCfg.Type)
 	}
 
 	return cnnstr, nil

pkg/services/sqlstore/tls_mysql.go

@@ -15,7 +15,7 @@ func makeCert(config DatabaseConfig) (*tls.Config, error) {
 	rootCertPool := x509.NewCertPool()
 	pem, err := ioutil.ReadFile(config.CaCertPath)
 	if err != nil {
-		return nil, fmt.Errorf("Could not read DB CA Cert path: %v", config.CaCertPath)
+		return nil, fmt.Errorf("could not read DB CA Cert path %q: %w", config.CaCertPath, err)
 	}
 	if ok := rootCertPool.AppendCertsFromPEM(pem); !ok {
 		return nil, err